China's coal mines produced about 390 million tons in September, 6.8% less than a year earlier, according to the National Bureau of Statistics, as safety checks kept a lid on supply just as thermal coal prices climbed to their highest in three years.

The squeeze matters well beyond China. Coal supplies nearly half of China's power, according to Oilprice.com, and tighter domestic supply tends to pull in seaborne cargoes from Indonesia and Australia, lifting prices for utilities in Japan, South Korea and Southeast Asia heading into the northern winter. It also feeds into the earnings of coal miners listed in Hong Kong, Shanghai and Jakarta.

Daily output averaged 12.84 million tons in September, the bureau said. Production for the first nine months fell 3.5% to 3.45 billion tons. The September decline was 0.9 percentage point smaller than in August, and output rose from the previous month, Bloomberg reported.

Clean power fills the gap left by hydro

China's large power producers generated 829.4 billion kilowatt-hours in September, down 1.2% from a year earlier, according to the statistics bureau. Generation for the year to date was still up 2.2%.

The mix shifted sharply. Hydropower fell 18.1%, which the Centre for Research on Energy and Clean Air (CREA), a research group, attributed largely to a 32% jump in September 2025 that made the comparison difficult. Nuclear output rose 21.5%, solar 19.5% and wind 10.6%, the bureau said. Thermal generation, mostly coal, slipped 1.4%.

CREA said coal-fired generation fell for a third straight month and that growth in solar, wind and nuclear "more than covered all additional electricity demand." The group's own estimate, which adds in smaller producers, put total generation up 1.2%. It also noted that China added a record 58.7 gigawatts of thermal power capacity in the first eight months of the year, a sign that coal plants are being built as backup even as they run less.

Other fuels showed the same caution. Crude oil processing fell 8.4% in September and natural gas output dipped 1.0%, the bureau said. CREA reported that coal imports fell 5.7% and crude imports 21.5% in the month.

Safety checks and thin port stocks lift prices

Supply has been the binding constraint. Annualized coal output has fallen since April, and the decline sped up after a deadly mine blast in Shanxi province in May prompted nationwide safety inspections, Bloomberg reported. Authorities have since urged Shanxi miners to raise supply.

Prices have responded. Benchmark thermal coal at Qinhuangdao rose for 11 straight weeks to a three-year high of 986 yuan a ton in late September, up about 24% from mid-July, Oilprice.com reported, citing Bloomberg data. Price reporter Mysteel assessed 5,500-kilocalorie coal at 1,026 yuan a ton free on board at northern ports on Oct. 16, its eighth straight daily gain, and tied the rally to a shrinking buffer of port stocks.

Seaborne supply has been tight as well. China's imports from Indonesia were down about a quarter this year, with lower government production quotas and low river levels from El Niño slowing barge traffic to export terminals, according to Oilprice.com. Indonesia is also reworking its domestic supply rules, including a plan to drop smelter power plants from its coal DMO.

What could ease the pressure

The China Coal Transportation and Distribution Association expects winter stockpiling to keep prices high through November, Bloomberg reported. The group sees little risk of a nationwide shortage now, but warned that regions with thin reserves could struggle and that steeper price gains could bring stronger government action to raise output. A return to monthly production of 420 million tons, last reached in March, could bring prices down, it said.

Analysts are divided on how quickly that happens. Nicole Li of consultancy OilChem said China could face a supply shortfall of 71 million tons this year, widening to 100 million tons in 2027, if the Middle East war keeps diverting coal into chemical plants as a substitute for oil, according to Bloomberg. Morgan Stanley analysts who visited Shanxi said the province's output could still fall 10% this year as miners act more cautiously under the safety rules.

Some factors work the other way. A slowing economy, relatively strong imports and forecasts of a milder winter have eased the strain, Bloomberg reported. Official data already point to softer industry: the factory purchasing managers' index fell to 49.3 in October.

The next test comes when the statistics bureau publishes October energy production. A monthly figure near 420 million tons would signal the mines are back to spring levels; another year-on-year drop would leave utilities in China and across Asia bidding for imported cargoes into the coldest months.